Finding the Fourth Proportional to 138.98, 209.21 and 126.68
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Solution
The fourth proportional to 138.98, 209.21 and 126.68 is: 190.69
Step by Step Solution
- Step 1: Write the proportion equation
138.98 : 209.21 = 126.68 : x - Step 2: Convert to fraction form
138.98/209.21 = 126.68/x - Step 3: Cross multiply
138.98x = 209.21 × 126.68 - Step 4: Simplify right side
138.98x = 26,502.22 - Step 5: Solve for x
x = 26,502.22/138.98 - Step 6: Final answer
x = 190.69
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These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.